基于斜坡单元下的AHP-信息量法在地质灾害易发性评价中的应用

APPLICATION OF AHP-INFORMATION METHOD IN GEOLOGICAL HAZARD SUSCEPTIBILITY EVALUATION BASED ON SLOPE UNIT

基于ArcGIS的地质灾害风险评价方法多种多样,但在致灾因素多样与复杂的沟谷地区,传统的易发性评价模型的评价精度难以满足实际需求.基于斜坡单元法的地质灾害易发程度分析可以充分体现控制因素和诱发因素的综合作用,而基于层次分析法(AHP)的信息量法既可以把灾害诱发因素按支配关系形成有序的分组和分层,又可以使统计分析评价与定量模型相结合,从而对斜坡体的评价更为有效,适用性更强.因此,本研究将基于斜坡单元的易发性评价方法与基于层次分析法的信息量法相结合,并加入斜坡类型评价因子,以陕西省略阳县灾害易发性评价区划为例,通过空间叠加分析得出易发评价区划并检验评价精度.研究结果符合实际情况,可为该地区地质灾害精细化评价和防灾减灾提供依据.

The accuracy of conventional susceptibility evaluation models cannot meet the actual needs in gully areas with diverse and complex disaster-causing factors despite various geological hazard risk assessment methods based on ArcGIS.The analysis of geohazard susceptibility based on slope element can fully reflect the combination of controlling and inducing factors,while the information method based on analytic hierarchy process(AHP)can not only form orderly groups and layers of disaster-inducing factors in terms of dominant relation,but also combine statistical analysis and evaluation with quantitative model,therefore the evaluation of slope body is more effective and more applicable.In this study,taking the disaster susceptibility evaluation zoning in Lueyang County of Shaanxi Province as an example,the combination of both methods above as well as slope type evaluation factor is used for prone area evaluation/division and verification of evaluation accuracy through spatial overlay analysis.The results are consistent with actual situation,which can provide basis for accurate evaluation and disaster prevention and mitigation of geohazards in the area.